The subject invention relates to a filter assembly, and in particular, to a filter assembly with radio frequency identification to assure that only a proper filter cartridge is inserted in the assembly.
Filter assemblies and filter cartridges are widely used to improve the taste and remove contaminants of drinking water and ice cubes. Filter cartridges may also be used to remove minerals to reduce the hardness of water and/or prevent staining. It is common for filter assemblies to include a housing that has fittings for attachment of a water line and is configured to receive a replaceable filter cartridge. Typically, one of the fittings will be an inlet fitting, and the other will be an outlet fitting, so that when the housing is connected in a water line, water will flow into the housing through the filter cartridge to be filtered and out the outlet fitting and back into the water line for use.
It is common that the filter cartridges are replaceable, as over a period of time and use, the filter's efficiency is reduced. The useful life may depend upon the quantity and type of contaminants in the water being filtered and the amount of water passed through the filter cartridge. Accordingly, most manufacturers typically advise replacing the filter cartridge with a new one after a certain period of time or after a pre-designated amount of water is filtered through the filter.
Furthermore, it may be desirable to use a different or specialized filter cartridge depending upon the region of the country, or local water conditions/amount and type of contaminants in the water. As is known in the art, certain types of filter cartridges are better for removing specific contaminants than others.
Accordingly, it would be desirable to provide a filter assembly that can identify whether the type of filter cartridge being inserted is the best or proper type for the specific water conditions.
The subject invention utilizes a Radio Frequency IDentifier/identification (RFID) for determining the presence or lack thereof of a proper or recommended filter cartridge. Although it is believed the disclosed use in a filter assembly is unique, RFID technology is well known for other uses. For example, RFID technology is common for improving the efficiency of inventory tracking and management; providing secured restricted entry into a building or room; for use in parking lots and garages to determine or identify authorized entrants, whereby upon making an RFID identification, a gate may be raised; or for providing identification of charge and/or debit cards. RFID functions rely on storing and remotely retrieving data using devices known as RFID tags or transponders. An RFID tag is a device that can be applied to or incorporated in a product or device to enable identification with the use of radio waves. The distance at which tags can be read varies, typically from an inch or two to several meters away from a reader.
Typically, RFID tags include at least two parts, one being an integrated circuit that stores and processes information to modulate and demodulate a radio frequency signal. The other part is in an antenna for receiving and transmitting a signal. Chipless RFID tags are also available that can provide discrete identification without the need of an integrated circuit, whereby the tags can be printed directly onto the desired device.
RFID tags are available in three general types. These include passive, active, or semi-passive, which are sometimes known as battery-assisted tags. Passive tags require no internal battery source and are powered by a reader attempting to read the tag. A passive RFID functions with the use of a minute electrical current that is induced in the tag's antenna by an incoming radio frequency signal. This provides just enough power for the integrated circuit in the tag to power up and transmit a response. One way this is accomplished is that the tag reader presents a field that excites a coil in the tag and charges a capacitor, which in turn energizes and powers the integrated circuit. The integrated circuit then transmits the identification number via a coil to the tag reader.
On the other hand, semi-passive and active tags require a power source, which is typically a small battery in order to transmit a response to the reader. Active and semi-active passive tags may transmit at higher power levels and at a greater range than passive tags; however, they tend to be larger in size and price than passive tags.